February 27, 1989
TO: X3T9.3 Committee
FROM: Roger Cummings
SUBJECT: EDITORIAL CHANGES TO ANSI X3.147-1988
The Level 3 Tape Working Group that met on February 1, 1989
recommended that the following EDITORIAL changes be made to the
document entitled Intelligent Peripheral Interface - Device
Generic Command Set for Magnetic Tapes (ANSI X3.147-1988):
1) That the section numbering be amended to correspond to
that in ISO DIS 9321 dated 21 August, 1988.
Specifically, this includes the following changes:
Section 4.1.1 becomes Section 4.4.1
Section 4.1.2 becomes Section 4.4.2
Section 4.1.3 becomes Section 4.4.3
Section 4.2 becomes Section 4.4.4
Section 4.3 becomes Section 4.4.5
Section 4.4 becomes Section 4.6.7
Section 4.5 becomes Section 4.13
Section 4.6 becomes Section 4.14
Section 4.7 becomes Section 4.15
Section 4.8 becomes Section 4.16
Section 8.3 becomes Section 8.4
Section 8.4 becomes Section 8.5
Section 8.5 becomes Section 8.6
Section 9.4 becomes Section 9.6
Section 9.5 becomes Section 9.7
Section 9.6 becomes Section 9.8
Section 10.2 becomes Section 10.3
Section 10.3 becomes Section 10.4
Section 10.4 becomes Section 10.5
Section 10.5 becomes Section 10.6
Section 10.6 becomes Section 10.7
Section 10.7 becomes Section 10.8
Section 10.8 becomes Section 10.9
Section 10.9 becomes Section 10.10
Section 10.10 becomes Section 10.11
Section 10.11 becomes Section 10.12
Section 10.12 becomes Section 10.13
Section 10.13 becomes Section 10.14
Section 10.14 becomes Section 10.15
Section 11.3 becomes Section 11.5
Section 11.4 becomes Section 11.6
Section 11.5 becomes Section 11.7
In addition sections 8.3, 8.7, 9.4, 9.5, 10.2, 11.3 and
11.4 become reserved.
2) That the table entry for parameter 5E in the Attributes
command (Table 4) be amended to have a length of "n+1"
and specified by "Both".
3) That the contents of Table 7 (Attribute Parm 68) and of
section 6.3.7 be amended to reference section 6.3.4.10
of ANSI X3.132-1987 and that the following paragraph be
added to section 6.3.7 - "This parameter has been
defined as "Both" for the purpose of commonality.
However in the Tape situation a Master would not
normally specify this parameter."
4) That Table 8 be amended to show Attribute parameter 69
as "reserved", and section 6.3.8.1 be renamed Parameter
69 and also identified as reserved.
5) That Section 6.4, Figure 3, and Table 15 be completely
replaced by Section 6.4, Figure 26, and Table 44 from
ANSI X3.132-1987 with the exception that the current
definition of the Media Status parameter (parm 52) is
retained from Table 15 and section 6.4.3. (Note that
the length of the Port Mask parameter in Table 44 will
also have to be corrected to "n+1".)
6) That the title of section 6.6 (and the entry in the
table of contents) be amended to Path Control.
7) That in Table 16 (Operating Mode Parms 3E-50) the entry
for Parameter 50 be amended to be specified by the
"Master".
8) That the following paragraph be added to section 6.10 -
"Note that in the Tape Situation, access permits are
normally defined on a partition basis only, and thus no
31, 32 and 3A parameters are used."
9) That new sections 6.12 and 6.13 be added, titled Port
Response and Anticipated Action respectively, which
reference the same sections in ANSI X3.132-1987.
10) That the Response Packet figure for all the commands in
Section 7 (excluding subsection 7.2) and Sections 8, 10
and 11 be amended to show a Major Status code of
"0001".
11) That all commands in sections 7, 8, 9, and 10 be
amended to include in their parameter list the Access
Key common parameter. Subsections describing the
parameter should be added which reference section 5.5.6
of ANSI X3.132-1987.
12) That the description of the Read command in section 8.1
be extended to include a parameter 51 named the
Information Transfer Size Override Parameter. This
should be listed in Table 23 and a subsection
describing the parameter should reference Section 8.1.4
of ANSI X3.132-1987.
13) That Section 8.1.5 and the entry in Table 23 for
parameter 52 be renamed the Master Termination
Permitted Parameter.
14) That in Figure 17 (Read Raw Data command packet) the
state of opmod bit 1 be amended as X and labelled Don't
Care.
Note that all of the above changes are also applicable to ISO
DIS 9321 dated 21 August, 1988 with the exception of #1, #6 and
#9, which have already been incorporated.
Please review the proposed changes, and be prepared to consider
their adoption at the plenary to be held in April at St.
Petersburg, FL.
If there are any problems or omissions I can be reached as
follows:
Phone: Business (416) 826-8640 x3332
Home (416) 625-4074 (ans machine)
Telex/MCI Mail: 650-289-5060 (USA)
Fax: (416) 821-6363
Regards
______________________
Roger Cummings
Principal Engineer, I/O and Peripherals
Systems and Strategies Group
Control Data Canada Ltd.
1855 Minnesota Court
Mississauga, Ontario L5N 1K7
Canada
#xs/rc
February 27, 1989
TO: X3T9.3 Committee
FROM: Roger Cummings
SUBJECT: EDITORIAL CHANGES TO ANSI X3.132-1987
The Level 3 Tape Working Group that met on February 1, 1989
recommended that the following EDITORIAL changes be made to the
document entitled Intelligent Peripheral Interface - Device
Generic Command Set for Magnetic Discs (ANSI X3.132-1987):
1) That the length of parameter 31 be amended from "09" to
"n+1" in the parameter lists of the following commands:
Position Control Table 53
Report Discontinuity Table 55
Read Table 56
Read Raw Data Table 58
Read Replicated Data Table 59
Search Table 60
Write Table 65
Write Pattern Table 66
Format Table 67
Reallocate Table 74
Allocate Restore Table 76
Read Verify Table 81
Read At First Available Data Table 82
Read From Buffer Table 83
Read Facility Data To Buffer Table 84
Read Physical Data and ECC Table 85
Read Physical Header Table 86
Read IPL Table 87
Read Physical Header and ECC Table 88
Write to Buffer Table 89
Write Buffer To Facility Table 90
Write Physical Data and ECC Table 91
Write Physical Header Table 92
Erase Table 94
Write Physical Header and ECC Table 95
2) That in Figure 56 (Read Raw Data command packet) the
state of opmod bit 1 be amended as X and labelled Don't
Care.
3) That Section 5.4.2.6.15 be amended by adding the words
"over the path of this command" to the end of the
existing paragraph.
4) That in Table 44 the length of parameter 50 be
corrected to "n+1".
5) That in section 6.8.4.2 the reference be corrected to
6.3.4.14.
Note that all of the above changes are also applicable to ISO
DIS 9320.
Please review the proposed changes, and be prepared to consider
their adoption at the April plenary in St. Petersburg, FL.
If there are any problems or omissions I can be reached as
follows:
Phone: Business (416) 826-8640 x3332
Home (416) 625-4074 (ans machine)
Telex/MCI Mail: 650-289-5060 (USA)
Fax: (416) 821-6363
Regards
______________________
Roger Cummings
Principal Engineer, I/O and Peripherals
Systems and Strategies Group
Control Data Canada Ltd.
1855 Minnesota Court
Mississauga, Ontario L5N 1K7
Canada
#xt/rc
February 27, 1989
TO: X3T9.3 Committee
FROM: Roger Cummings
SUBJECT: TECHNICAL CHANGE TO ANSI X3.147-1988
The Level 3 Tape Working Group that met on February 1, 1989
recommended that the following TECHNICAL change be made to the
document entitled Intelligent Peripheral Interface - Device
Generic Command Set for Magnetic Tapes (ANSI X3.147-1988):
That the contents of Section 11.3 be completely replaced by
the following text:
This command is identical to the READ ERROR LOG command
in 11.5 of ANSI X3.132-1987 and the same requirements
shall apply.
Note that in an earlier ANSI published version instead
of referencing ANSI X3.132-1987 an outdated version of
the Read Error Log command was mistakenly included. The
outdated version differed substantially from ANSI
X3.132-1987 in the areas of the operation modifier bits
and the parameter list.
In addition that the contents Figure 29 be replaced by the
contents of Figure 120 from ANSI X3.132-1987, and that the
contents of Table 29 be replaced by the contents of Table
102 from ANSI X3.132-1987.
Note that the above change is also applicable to ISO DIS 9321
dated 21 August, 1988.
Please review the proposed change, and be prepared to consider
their adoption at the April plenary in St. Petersburg, FL.
If there are any problems or omissions I can be reached as
follows:
Phone: Business (416) 826-8640 x3332
Home (416) 625-4074 (ans machine)
Telex/MCI Mail: 650-289-5060 (USA)
Fax: (416) 821-6363
Regards
______________________
Roger Cummings
Principal Engineer, I/O and Peripherals
Systems and Strategies Group
Control Data Canada Ltd.
1855 Minnesota Court
Mississauga, Ontario L5N 1K7
Canada
#xu/rc
February 27, 1989
TO: X3T9.3 Committee
FROM: Roger Cummings
SUBJECT: ENHANCEMENT TO TRANSFER PARAMETER
The Level 3 Tape Working Group that met on February 1, 1989
recommended that the following ENHANCEMENT be made to the
document entitled Intelligent Peripheral Interface - Device
Generic Command Set for Magnetic Disk (ANSI X3.132-1987):
1) That the contents of Table 23 be replaced with the
following:
+-+---+--+-----+---+---+
|@|LTH|ID|OCTET|X/b|DEF| TRANSFER PARAMETERS
+-+---+--+-----+---+---+--------------------------------------------
|M| 04|3C| 01| | | Write Transfer Controls
| | | | | 7| | Verify
| | | | | 6| | Volume
| | | | | 5| | Certify
| | | | | 4| | Stop on Data Error
| | | | | 3| | reserved
| | | | | 2| | reserved
| | | | | 1| | Compare - use buffer under slave control *
| | | | | 0| | Compare - Master repeat transfer *
| | | | | | |
| | | | 02| | | Read Transfer Controls
| | | | | 7| | Threshold
| | | | | 6| | Suppress Incorrect Length Indication (SILI)
| | | | |5-0| | reserved
| | | | | | |
| | | | 03| | | Response Conditions
| | | | | 7| | Post Conditional Success if Error Retry
| | | | | 6| | Post Conditional Success if Data Correction
| | | | | 5| | Inhibit Operation Response on Success
| | | | | 4| | Inhibit Extended Substatus Response
| | | | |3-0| | reserved
| | | | | | |
| | | | | | | * mutually exclusive parameters
+-+---+--+-----+---+---+--------------------------------------------
2) That the following new subsections be added to Section
5.5.13:
5.5.13.6 Threshold
If the Threshold modifier is set, then the contents of
the Count field in the Command Extent Parameter of the
current command shall be interpreted as a 'threshold'
such that, in the presence of no errors:
a) If the number of octets in the block is less than
or equal to the threshold, then the entire block
is transferred normally and a Command Completion
Response indicating Successful and containing a
Response Extent parm with a residual count
(Threshold - Number of Octets Transferred) shall
be returned by the Slave. The chain shall not be
broken and all subsequent commands shall execute
normally.
b) If the number of octets in the block is greater
than the threshold, then the part of the block up
to the threshold count is transferred and a
Command Completion Response indicating Incomplete
Status with the Block Length Difference bit set
and containing a Response Extent parm with a zero
residual count shall be returned by the Slave,
thus breaking the chain. After the completion of
the command, positioning shall be as after a
non-threshold command.
In all other respects the command shall operate as
normal.
The Threshold modifier is only significant if the Count
field is specified as being in units of an octet.
Note that this modifier is normally only used with
devices that operate on variable-sized blocks e.g.
variable-sized records on tape.
5.5.13.7 Suppress Incorrect Length Indication
If the Suppress Incorrect Length Indication modifier is
set, then no error indication shall be returned by the
Slave as a result of the block size transferred to the
Master differing from the count specified in the
Command Extent Parameter. No residual count will be
transferred.
5.5.13.8 Response Conditions (Octet 3 bits 7-4)
The master can override the setting in attributes, for
the duration of this command, by the use of these
modifiers. They have the same meanings as the bits
defined in the Slave Reconfiguration Parameter of the
ATTRIBUTES command (6.3.4.14).
3) That the Transfer parameter be added to the parameter
list of all commands in sections 7, 8, 9 and 10 in
which it does not already appear.
Please review the proposed enhancement, and be prepared to
consider its adoption at the April plenary in St. Petersburg, FL.
If there are any problems or omissions I can be reached as
follows:
Phone: Business (416) 826-8640 x3332
Home (416) 625-4074 (ans machine)
Telex/MCI Mail: 650-289-5060 (USA)
Fax: (416) 821-6363
Regards
______________________
Roger Cummings
Principal Engineer, I/O and Peripherals
Systems and Strategies Group
Control Data Canada Ltd.
1855 Minnesota Court
Mississauga, Ontario L5N 1K7
Canada
#xv/rc
February 27, 1989
TO: ANSI X3T9.3 Committee Members
FROM: Roger Cummings
SUBJECT: ALTERNATE DEFERRED ERROR HANDLING
The Level 3 Tape Working Group that met on February 1, 1989
recommended that the following ENHANCEMENT be made to the
document entitled Intelligent Peripheral Interface - Device
Generic Command Set for Magnetic Disk (ANSI X3.132-1987):
That section 4.6 be replaced with the following text:
4.6 Data Buffer Operation
A tape slave/facility may contain buffer space capable of
containing multiple blocks of data. This data buffer may contain
data "read ahead" from the medium or data waiting to be written
to the medium.
When performing a write, a slave/facility capable of storing
multiple blocks in the data buffer may:
a) Transfer an operation response indicating Successful status to
the master once all the write data has been transferred from the
master and successfully stored in the data buffer. If an
unrecoverable write error is subsequently encountered while
attempting to record the data on the medium, the addressee shall
generate an Asynchronous Response packet to inform the master of
the failure. The master may then use the REPORT POSITION command
to determine the number and addresses of the data blocks
remaining to be fixed to tape. Unwritten data may then be
recovered by using the READ FROM BUFFER command.
or, alternatively:
b) Transfer an operation response indicating Successful status to
the master only when all of the write data has been successfully
written to the media. If an unrecoverable error occurs anywhere
in this process, then the operation response (command completion)
indicates the error to the master as usual. The Master may then
be able to determine the media position from the CRN in the
response packet, or it may have to issue a REPORT POSITION
command. The master may then reset the addressee to clear the
buffer contents, and may reissue the data that was not written on
the media to the same or different media. This alternative may be
useful in journalling applications in which the performance
degradation of true synchronous mode due to multiple repositions
is unacceptable. Note however that implementations that use this
alternative must carefully consider the impact of the depth of
their command queues on the usable size of their data buffer.
Note also that this alternative combined with the supression of
Operation Responses on Successful is almost equivalent to
alternative a) above.
Addressees that "read ahead" into a data buffer shall not report
an unrecoverable read error to the master until the unrecoverable
data is requested by the master.
Tape slaves/facilities that provide the asynchronous buffer mode
shall also support a synchronous mode of operation that may be
controlled by the master (i.e. the addressee shall be capable of
disabling the data buffer). Enabling and disabling the data
buffer is accomplished using the ATTRIBUTES and OPERATING MODE
commands. In addition, a master may instruct an addressee,
operating in the asynchronous mode, to synchronize its buffer and
media position by issuing a POSITION CONTROL command with the
Synchronize bit asserted.
Please review the proposed enhancement, and be prepared to
consider its adoption at the April plenary in St. Petersburg, FL.
If there are any problems or omissions I can be reached as
follows:
Phone: Business (416) 826-8640 x3332
Home (416) 625-4074 (ans machine)
Telex/MCI Mail: 650-289-5060 (USA)
Fax: (416) 821-6363
Regards
______________________
Roger Cummings
Principal Engineer, I/O and Peripherals
Systems and Strategies Group
Control Data Canada Ltd.
1855 Minnesota Court
Mississauga, Ontario L5N 1K7
Canada
#xw/rc